The invention pertains to medical devices and more particularly to devices for anchoring a catheter when inserted in the body so that the catheter does not rest against or puncture a vein wall.
Infusion sets have been used in the medical world for many years to introduce and remove fluids from a patient""s body. The set typically consists of a catheter or hollow needle mounted to a backing pad, a length of tubing connected at a first end to the catheter, and a connection fitting attached to a second end of the tubing. The catheter is inserted into a patient""s vein and the backing pad is then secured to the patient""s skin, usually with surgical tape. A supply of fluid to be infused into the patient is connected to the connection fitting and allowed to flow, by means of gravity, through the tubing, into the catheter and into the patient""s vein.
If the backing pad is not properly secured to the patient""s skin, the catheter may be dislodged. Further, if the angle at which the catheter is inserted into the patient""s vein is not maintained, it is possible for the catheter to puncture a lower wall of the vein, preventing effective introduction of the infusion fluid into the patient""s vein. A means of anchoring the catheter securely in place is needed to avoid dislodging or movement of the catheter by the patient.
The prior art includes a number of inventions directed towards stabilizing a catheter or needle inserted into a patient. U.S. Pat. No. 4,197,890 issued to Gordon et al in 1982 covers a winged fitting for use in intravascular needle or catheter insertion and subsequent stabilizing of the connection to the patient""s skin. U.S. Pat. No. 5,156,641 issued to White et al. in 1992 provided for a naso-gastric catheter anchor system. The system employs a bilaterally symmetrical butterfly outline adhesive nose anchor. The anchor would affix a flexible small bore tubing to the nose.
U.S. Pat. No. 5,413,562 issued to Swauger in 1995 describes a stabilizing fitting for an intravenous catheter or syringe. The stabilizing fitting is anchored in place with velcro straps about the limb instead of a locally applied adhesive. Likewise, U.S. Pat. No. 5,449,349 issued to Sallee et al. in 1995 is directed towards an intravenous needle cover/protector. The catheter is housed within the device that is taped to the patient""s skin.
U.S. Pat. No. 5,370,627 issued to Conway in 1994 illustrates a securing bridge for a catheter inserted directly into the umbilical stump of a neonate. The bridge includes a base onto which adhesive tape could be employed to secure the device to the neonate""s skin.
Of a slightly different nature, U.S. Pat. No. 4,820,282 issued to Hogan in 1987 relates to a sheath for use in removing hypodermic needles from patients and retaining the point of the removed needle in the sheath when the needle and sheath are disposed of so as to protect against accidentally being pricked.
Of a very different nature is U.S. Pat. No. 4,898,587 issued to Mera in 1990. The Mera invention comprises a base plate, which includes a crotch, and a channel in its upper serface; and a cover. The base plate is designed to adhere on its underside to the patient""s skin. The crotch is designed to fit around a catheter inserted into a vein and the tubing is retained in the channel with adhesive tape. The cover is then secured to the base plate for added protection.
It is an objective of the invention to provide a means to quickly and effectively attach a catheter and the backing pad of a butterfly infusion set to the skin of a patient. It is a further objective of the invention to stabilize and control the angle at which the catheter is maintained within the vein of a patient, so as to prevent accidental puncturing of the vein wall during subsequent infusion. It is yet a further objective of the invention to prevent the vein wall from being drawn into the catheter when the infusion set is used as a blood drawing device. It is still a further objective of the invention that the butterfly anchor is simple and inexpensive to manufacture.
A butterfly anchor for an infusion set may be constructed from the following components. A flexible catheter anchor pad sized and shaped to cover the backing pad of a butterfly infusion set. The anchor pad extends beyond the perimeter of the backing pad for a first predetermined distance. The first predetermined distance must be sufficient so that the anchor pad and backing pad do not lift during service. The anchor pad has a top surface and a bottom surface. The bottom surface includes a means for attachment to the skin of a patient and the backing pad. Reinforcing means are attached to the anchor pad, spaced apart from the center line of the anchor pad.
In use, when the backing pad of a butterfly infusion set is secured to the skin of a patient by the butterfly anchor, the reinforcing means will prevent the catheter of the infusion set from resting against or puncturing the vein wall during subsequent patient movement.
In a variant of the invention, the means for attachment is an adhesive located on the bottom surface of the anchor pad.
In another variant of the invention, the reinforcing means includes at least one rigid longitudinal element affixed to the anchor pad. The longitudinal element is oriented so as to be parallel to a long axis of the catheter when the anchor pad is attached to the backing pad of an infusion set.